Dual bios

[agros]

Suppose there is a second bios. How do I enable it?

Something strange happens, in bios I set first boot device the cd, but wont work.
I reset to factory defaults and works. But that's because its now in ide mode. If I set it in ahci mode, cd boot wont work.

Can some1 help?

[klh591]

CD and DVD drives don't like AHCI. They need to be connected to motherboard connecters that are set in the BIOS to IDE mode only, usually
connecters 4 and 5 or 6 and  7, depending on how many connecters your motherboard has.

After making this change in the BIOS I've never had a problem on any of my boards ( Currently 4- 970A-UD3, 3- 990FXA-UD3, and 2- 990FXA-UD5 ).

[agros]

I see. So there are ports 5 & 6 which I set them as ide. Now cd boot is possible, while other ports are as ahci.

But then I get this msg (I try install Win7-64, not a clean new installation)

The following issues are preventing Windows from upgrading. Cancel the upgrade, complete each task, and then restart the upgrade to continue.  
You can’t upgrade 64-bit Windows to a 32-bit version of Windows. To upgrade, obtain a 64-bit version of the installation disc, or go online to see how to install Windows 7 and keep your files and settings.
32-bit Windows cannot be upgraded to a 64-bit version of Windows. To upgrade, obtain a 32-bit version of the Windows installation disc.

I have a Win 64 dvd and the existing installation is 64.
What could I do about?

[thexfile]

Don't forget to do this..
http://www.everything-microsoft.com/2010/05/25/how-to-enable-ahci-in-windows-7/

[agros]

This is to set ahci after the installation. I always set ahci before the installation